A review on paleoenvironment suitability for hominid fossils and other early vertebrate faunas: a case from Pucangan and Kabuh Formations, Central and East Java, Indonesia

Rubiyanto Kapid,Johan Arif,Dasapta Erwin Irawan

doi:10.14293/s2199-1006.1.sor-life.ah9puy.v1

Abstract

Abstract The northern part of the East Java Basin has become a focus of research by earth scientists, among others, because of the existence of hominid fossils and remains of other vertebrate taxa within the Quaternary sedimentary sequence. Fossil-bearing layers are found in the Kendeng Zone, mostly within the well-known Pucangan and Kabuh Formations, which are distributed from Central to East Java. However, not all formations contain vertebrate fossils as well as hominid elements. It is important to consider what factors may have influenced the concentration of vertebrate fossils in those formations. In this study, we describe sedimentary facies at three key field locations: Sangiran, Ngawi, and Mojokerto. Our study indicates that vertebrate remains and hominid fossils mainly accumulated in continental sediments associated with lacustrine and fluvial systems. In this regard, Sangiran and Ngawi B offer the greatest prospect for yielding hominid remains, owing to their unique paleoenvironmental and paleogeographical settings as a highland during the Early–Middle Pleistocene period. Certain parts of the Kabuh Formation in the Mojokerto region also hold high potential, especially those displaying evidence of continental deposition.

Highlights

The northern part of the East Java Basin has become a focus of considerable interest to earth scientists due to the existence of oil and gas resources, and a continuous sequence of sedimentary layers from Mid-Miocene to Pleistocene in age, some of which have yielded fossils of early hominids as well as a wide range of other vertebrate fossils which occur in certain Quaternary sediments
The Pucangan and Kabuh Formations extend through the Kendeng Zone, raising the question of why hominid and other vertebrate fossils found within these formations are mostly concentrated within the Sangiran area only
Sangiran area Located on the eastern end of West Kendeng, Sangiran is one of the world’s most longstanding and celebrated sources of

Summary

Introduction

The northern part of the East Java Basin (the area between 110°30' to 113° E and 6°22' and 7°41' S) has become a focus of considerable interest to earth scientists due to the existence of oil and gas resources, and a continuous sequence of sedimentary layers from Mid-Miocene to Pleistocene in age, some of which have yielded fossils of early hominids as well as a wide range of other vertebrate fossils which occur in certain Quaternary sediments. The Pucangan and Kabuh Formations extend through the Kendeng Zone, raising the question of why hominid and other vertebrate fossils found within these formations are mostly concentrated within the Sangiran area only. In the Sangiran area, the Pucangan Formation consists of the following three lithological components (from lower to upper): lower volcanic breccia, diatomaceous clay member, and black clay member (see Figure 3).

Results

Conclusion